Dollar General said it would adding more employees to the front of its stores.Justin Sullivan/Getty ImagesRetail's self-checkout reckoning has arrived for Dollar General.The discount store said Thursday it would beef up staffing, aiming to boost sales and reduce theft.CEO Todd Vasos said the company "started to rely too much this year on self-checkout in our stores."Add Dollar General to the list of retailers rethinking their self-checkout strategies as they head into the new year.The discount retailer said Thursday it will beef up staffing in its stores' checkout areas after the company reported slowing sales growth and rising rates of missing inventory, or shrink."While self-checkout has contributed to the convenient proposition for our customers in certain stores, it does not reduce the importance of a friendly, helpful employee who is there to greet customers and assist while the checkout process is happening," Dollar General CEO Todd Vasos said on the company's quarterly earnings call.Vasos said Dollar General is budgeting $150 million in additional labor hours, as well as reallocating $50 million from the "smart teams" unit to cover the added staffing expenses.